The present invention is directed to the field of sound systems. More particularly, the present invention is directed to a rigging system for forming speaker arrays which includes a lever arm which facilitates the movement of a portion of the array to improve sound quality of the sound system.
When sound systems are “built” in a large amphitheater or auditorium, the use of multiple speakers has the potential to create acoustical problems. Speaker arrays are focused to provide even coverage in the audience area and fine tune the sound distribution, avoiding bouncing the sound off the ceiling and walls. The sound will be focused, directed, toward the rear of house with lesser amounts of concentrated sound energy aimed at the front of the house, due to the audience's proximity to the speakers.
It is often the case that speakers are stacked 6, 8 or 12 or more, high. These stacks may be floor mounted or suspended from a ceiling bracket or mount. (Typically floor mounted stacks will not exceed 6 speakers, for safety reasons.) Use of spacers or shims is problematic, at best, and the need to move the speaker stack to accommodate such wedges increases the difficulty. Some rigging systems afford the ability to more easily adjust the angularity of adjacent speakers by relocating fasteners in the sides of the cabinet to permit tilting of one speaker relative to another. This is obviously a step up from the use of shims. However, the movement of a stack of speaker is still an issue; the stack, whether ground mounted or suspended, must be dismounted and laid down on its side to permit splay angles to be adjusted by pulling the securement pin and positioning it in an alternate hole. This is not just an operational headache. Movement of these stacks to lay them down and stand them up, present significant safety issues for the rig hands. Further, repeated adjustments necessary to focus the system and fine tune the coverage is made all the more difficult in the trial-and-error process.
The present invention seeks to address this problem. The rigging itself incorporates a lever arm which facilitates the pivotal movement of one or more speakers to readily permit focusing or re-aiming the system. The present invention comprises a rigging system for speaker cabinets in a stack comprising a) a generally rectangular bracket having means to attach the bracket to a side panel of a first one of the speaker cabinets; b) a rear tie bar pivotally attached to an upper, rear portion of the bracket with a first arm extending upwardly for attachment to a second adjacent speaker cabinet above the first speaker cabinet in the stack; c) a front tie bar pivotally attached to an upper, forward portion of the bracket with a second arm extending upwardly for attachment to the second adjacent speaker cabinet above the first speaker cabinet in the stack; d) a lever arm having a first upper end which can be secured to a number of different arcuately spaced positions on a forward portion of the bracket and a second lower end which is pivotally attached to a lower rear portion of the bracket at a first pivot point and attachable to said rear tie bar of a third adjacent speaker cabinet below the first cabinet in the stack at a second pivot point axially spaced from the first pivot point creating a moment arm such that when the lever arm is pivoted downwardly relative to said bracket from a first arcuately spaced position to a second arcuately spaced position, the moment arm enables the first speaker cabinet and all cabinets supported thereby to be rotated around a front edge by a first desired angular amount.
The rigging system employs both a first bracket for a first side as well as a second bracket attachable to a second side of the speaker cabinet. The bracket may more accurately be described as substantially trapezoidal. The first arm of the rear tie bar preferably has at least one additional pivot attachment point which adds angular adjustment when the second end of said lever arm is pivotally attached thereto. When the stack of speaker cabinets is suspended from a ceiling mount, all the cabinets supported by the first cabinet are those cabinets below the first speaker cabinet. When the stack of speaker cabinets is attached to a floor mount, all the cabinets supported by the first cabinet are those cabinets above the first speaker cabinet. It is an additional feature of the rigging system of the present invention that the front tie bar includes means to angularly adjust the position of the second speaker positioned above the first speaker cabinet to which it is attached.
Various other features, advantages and characteristics of the present invention will become apparent to one of ordinary skill in the art after a reading of the following specification.